package com.example.server.controller;

import com.google.code.kaptcha.impl.DefaultKaptcha;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;

/**
 * 验证码
 */
@RestController
public class CaptchaController {

    @Autowired
    private DefaultKaptcha defaultKaptcha;

    @ApiOperation(value = "验证码")
    @GetMapping(value = "/captcha",produces = "image/jpeg")
    public void captcha(HttpServletRequest  request, HttpServletResponse  response) throws Exception{
        //定义response输出类型为image/jpeg类型
        response.setDateHeader("Expires", 0);
        //Set standard HTTP/1.1 cache control directives for an entity that is not always changing.
        response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
        //Set IE extended HTTP/1.1 cache control directives for an entity that is not always changing.
        response.addHeader("Cache-Control", "post-check=0, pre-check=0");
        //Set standard HTTP/1.0 timer.
        response.setHeader("Pragma", "no-cache");
        //return a jpeg
        response.setContentType("image/jpeg");

        //===================生成验证码begin=====================
        //获取验证码文本
        String text =defaultKaptcha.createText();
        System.out.println("验证码内容："+ text);
        //将验证码文本保存到session中
        request.getSession().setAttribute("captcha", text);
        //根据文本验证码内容创建图形验证码
        BufferedImage image = defaultKaptcha.createImage(text);
        ServletOutputStream outputStream = null;
        try {
            outputStream = response.getOutputStream();
            //输出流输出图片
            ImageIO.write(image, "jpg", outputStream);
            outputStream.flush();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (outputStream != null) {
                try {
                    outputStream.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
        //===================生成验证码end=====================

    }
}
